The natural world is full of many fabulous and mysterious objects, but few of them can rival the truly gargantuan crystals resting nearly a thousand feet beneath the ground in Naica, Mexico.
Those who travel deep into the Earth to catch a glimpse of "Cueva de los Cristales," or "The Cave of Crystals," are typically left awestruck by the dazzling sight.
But although the sight may be breathtaking, taking it in is not for the faint of heart.
According to National Geographic:
It takes 20 minutes to get to the cave entrance by van through a winding mine shaft. A screen drops from the van's ceiling and Michael Jackson videos play, a feature designed to entertain visitors as they descend into darkness and heat. In many caves and mines the temperature remains constant and cool, but the Naica mine gets hotter with depth because it lies above an intrusion of magma about a mile below the surface. Within the cave itself, the temperature leaps to 112 degrees Fahrenheit with 90 to 100 percent humidity—hot enough that each visit carries the risk of heatstroke. By the time we reach the entrance, everyone glistens with sweat.
Though the journey may be long and risky, anyone who has beheld the crystals in person will tell you that the otherworldly sight is worth the trek.
"I crawled among the world's largest crystals, a forest of them, broad and thick, some more than 30 feet long and half a million years old," wrote journalist Neil Shea of her experience in the cave. "So clear, so luminous, they seemed extraterrestrial."
More footage inside the incredible cave: